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This paper presents Etest determinations of MICs of selected antimicrobial agents for 76 isolates of Bacillus anthracis chosen for their diverse histories and 67, 12, and 4 cultures, respectively, of its close relatives B. cereus, B. thuringiensis, and B. mycoides derived from a range of clinical and environmental sources. NCCLS breakpoints are now available for B. anthracis and ciprofloxacin, penicillin, and tetracycline; based on these breakpoints, the B. anthracis isolates were all fully susceptible to ciprofloxacin and tetracycline, and all except four cultures, three of which had a known history of penicillin resistance and were thought to originate from the same original parent, were susceptible to penicillin. Based on NCCLS interpretive standards for gram-positive and/or aerobic bacteria, all cultures were susceptible to amoxicillin-clavulanic acid and gentamicin and 99% (one with intermediate sensitivity) of cultures were susceptible to vancomycin. No group trends were apparent among the different categories of B. cereus (isolates from food poisoning incidents and nongastrointestinal infections and food and environmental specimens not associated with illness). Differences between B. anthracis and the other species were as expected for amoxicillin and penicillin, with all B. anthracis cultures, apart from the four referred to above, being susceptible versus high proportions of resistant isolates for the other three species. Four of the B. cereus and one of the B. thuringiensis cultures were resistant to tetracycline and a further six B. cereus and one B. thuringiensis cultures fell into the intermediate category. There was a slightly higher resistance to azithromycin among the B. anthracis strains than for the other species. The proportion of B. anthracis strains fully susceptible to erythromycin was also substantially lower than for the other species, although just a single B. cereus strain was fully resistant. The Etest compared favorably with agar dilution in a subsidiary test set up to test the readings, and it compared with other published studies utilizing a variety of test methods.

Antibiotic susceptibilities were determined for 122 Neisseria gonorrheae isolates obtained from 400 sex workers in Jakarta, Indonesia, and susceptibilities to ciprofloxacin, cefuroxime, cefoxitin, cefotaxime, ceftriaxone, chloramphenicol, and spectinomycin were found. All isolates were resistant to tetracycline. A number of the isolates demonstrated decreased susceptibilities to erythromycin (MIC >/= 1.0 microg/ml), thiamphenicol (MIC >/= 1.0 microg/ml), kanamycin (MIC >/= 16.0 microg/ml), penicillin (MIC >/= 2.0 microg/ml), gentamicin (MIC >/= 16.0 microg/ml), and norfloxacin (MIC = 0.5 microg/ml). These data showed that certain antibiotics previously used in the treatment of gonorrhea are no longer effective.

Among a United States military unit of 170 personnel deployed to Utapao, Thailand for a three-week training exercise, 40% experienced diarrheal disease, and 12% sought medical treatment for diarrhea. Most illness clustered within the first two weeks of arrival and individuals were ill an average of 3.6 days. Fifty-five percent of cases lost two days of work and 15% required treatment with intravenous fluids. Bacterial pathogens were recovered from 38% of 16 stools submitted, with Campylobacter jejuni the most common. Four (12.5%) of 32 persons who voluntarily submitted paired sera exhibited a four-fold increase in IgG antibody titer to C. jejuni. Traveler's diarrhea continues to be an important problem with a serious potential to impact the mission readiness of even small military units deployed overseas.

A community-based prospective study was performed from December 1993 through March 31, 1994 in Indonesia in children less than five years of age. Enterotoxigenic Escherichia coli (ETEC) was identified in diarrheic stool by colony hybridization assay, using toxin probes, and this bacterium was isolated from 19% of 340 episodes of diarrhea. Sixty-one percent of ETEC produced heat-labile toxin (LT) only, 325 LT and heat-stable toxin (ST), and 75 ST only. The age-specific incidence rates of diarrhea among children 0-1 and 2-3 years of age were 77% and 61%, respectively, during the study period; ETEC was isolated from 26% of children 0-1 years of age versus 53% for children 2-3 years of age. As many as seven episodes of diarrhea were repeatedly experienced by a single child during the four-month study period; however, only two children had more than one episode of known ETEC-associated diarrheal disease during the period of observation.

Strong positive CAMP reactions were demonstrated by 121 Vibrio cholerae O139 and 504 El Tor isolates, and weak positive CAMP reactions were shown by 235 non-O1, non O139 isolates when these isolates were tested by a modified CAMP technique. Thirty-five classical biotype V. cholerae O1 isolates included in the tests were all CAMP negative.

Mold growth and mycotoxin production were studied in high-moisture (20%) corn treated with tetrasodium pyrophosphate (TSPP); acid and alkaline sodium polyphosphate, glassy (SPG), also known as sodium hexametaphosphate; sodium tripolyphosphate (STPP); and tricalcium phosphate. Six mold cultures belonging to the genera Aspergillus , Fusarium , and Penicillium were tested in corn varieties highly resistant or highly susceptible to mold infection in the field, and in a mixture of five other varieties of corn. The acidic SPG, as well as TSPP and STPP totally prevented or reduced mold growth when added in powder form to corn at 1.0% or 2.0% (w/w), regardless of corn variety and high moisture content. Phosphates afforded protection in whole and damaged kernels. Similar results were obtained with 2.0% acidic SPG and TSPP when added in spray form. Whenever mold growth occurred, treatment of corn with 1.0% or 2.0% (w/w) TSPP and acidic or alkaline SPG inhibited (P<0.01) aflatoxin production by aspergilli.

Mycelial growth and mycotoxin production of Aspergillus flavus and A. parasiticus were studied in Sabouraud dextrose agar containing pure or blended pyro-, poly- or meta-phosphates during 9 d of incubation at 30°C. Pure tetrasodium pyrophosphate (TSPP) and sodium polyphosphate, glassy (SPG, formerly hexametaphosphate), as well as a commercial phosphate blend and three combinations all containing various proportions of sodium acid pyrophosphate (SAPP), TSPP and SPG were tested. Inhibition of growth of aspergilli was observed in media containing 2.0% TSPP and 1.0 and 2.0% SPG and 2.0% of the commercial phosphate blend. Lower concentrations of single or blended phosphates allowed only limited, atypical mycelial growth. Sporulation was totally inhibited by 2.0% concentrations of single or blended phosphates, and so was production of aflatoxins B 1 and G 1 . TSPP or SPG at 1.0% reduced (P<0.05) aflatoxin production from parts per million (controls) to parts per billion.